<?php
/**
 * PHP version 5.3.x
 *
 * @category
 * @package
 * @author   gouki <gouki.xiao@gmail.com>
 */
/**
 * SaeMemcache.php
 *
 * @category
 * @package
 * @author   gouki <gouki.xiao@gmail.com>
 * @version  $Id$
 * @created  2011-11-22 23:53
 */
class SaeMemcache extends CMemCache {
    private $_cache = null;
    public function init() {
        $this->getMemCache();
    }
    public function getMemCache() {
        if ($this->_cache !== null) {
            return $this->_cache;
        }
        else {
            return $this->_cache = memcache_init();
        }
    }
    public function getServers() { }
    public function setServers($config) { return; }
    /**
     * Retrieves a value from cache with a specified key.
     * This is the implementation of the method declared in the parent class.
     *
     * @param string $key a unique key identifying the cached value
     *
     * @return string the value stored in cache, false if the value is not in the cache or expired.
     */
    protected function getValue($key) {
        return $this->_cache->get($key);
    }
    /**
     * Retrieves multiple values from cache with the specified keys.
     *
     * @param array $keys a list of keys identifying the cached values
     *
     * @return array a list of cached values indexed by the keys
     * @since 1.0.8
     */
    protected function getValues($keys) {
        return $this->useMemcached ? $this->_cache->getMulti($keys) : $this->_cache->get($keys);
    }
    /**
     * Stores a value identified by a key in cache.
     * This is the implementation of the method declared in the parent class.
     *
     * @param string  $key    the key identifying the value to be cached
     * @param string  $value  the value to be cached
     * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
     *
     * @return boolean true if the value is successfully stored into cache, false otherwise
     */
    protected function setValue($key, $value, $expire) {
        if ($expire > 0) {
            $expire += time();
        }
        else {
            $expire = 0;
        }
        return $this->useMemcached ? $this->_cache->set($key, $value, $expire)
                : $this->_cache->set($key, $value, 0, $expire);
    }
    /**
     * Stores a value identified by a key into cache if the cache does not contain this key.
     * This is the implementation of the method declared in the parent class.
     *
     * @param string  $key    the key identifying the value to be cached
     * @param string  $value  the value to be cached
     * @param integer $expire the number of seconds in which the cached value will expire. 0 means never expire.
     *
     * @return boolean true if the value is successfully stored into cache, false otherwise
     */
    protected function addValue($key, $value, $expire) {
        if ($expire > 0) {
            $expire += time();
        }
        else {
            $expire = 0;
        }
        return $this->useMemcached ? $this->_cache->add($key, $value, $expire)
                : $this->_cache->add($key, $value, 0, $expire);
    }
    /**
     * Deletes a value with the specified key from cache
     * This is the implementation of the method declared in the parent class.
     *
     * @param string $key the key of the value to be deleted
     *
     * @return boolean if no error happens during deletion
     */
    protected function deleteValue($key) {
        return $this->_cache->delete($key, 0);
    }
    /**
     * Deletes all values from cache.
     * This is the implementation of the method declared in the parent class.
     *
     * @return boolean whether the flush operation was successful.
     * @since 1.1.5
     */
    protected function flushValues() {
        return $this->_cache->flush();
    }
}
